Popular gaming marketplace Steam is ready to be the third major desktop application store, next to Apple’s App Store and Microsoft’s upcoming Windows 8 store. Valve, the parent company of Steam, announced in a press release this afternoon the arrival of new non-gaming software on its store that will launch Sept. 5. It is a certain step away from its years of focusing on just gaming. Steam will offer apps ranging from “creativity to productivity,” and they will be organized into categories, as shown off in a leaked screenshot above of Steam’s iOS app from June. Steam will also include its Steamworks feature in the store. It allows for automatic updating of apps and the ability to save data to the Steam Cloud. [Joystiq]

Steam initially launched in September 2003 as a market to distribute games and a community for gamers to play. As of this month, over 1,500 games are available with over 54 million active users across the network. Steam launched for OS X in March 2010.

Developers looking to have their software available on Steam can now submit it for the September 5 launch through the Steam website. Is anyone excited?

Aug 8, 2012 — Valve, creators of best-selling game franchises (such as Counter-Strike, Half-Life, Left 4 Dead, Portal, and Team Fortress) and leading technologies (such as Steam and Source), today announced the first set of Software titles are heading to Steam, marking a major expansion to the platform most commonly known as a leading destination for PC and Mac games.

The Software titles coming to Steam range from creativity to productivity. Many of the launch titles will take advantage of popular Steamworks features, such as easy installation, automatic updating, and the ability to save your work to your personal Steam Cloud space so your files may travel with you.

More Software titles will be added in an ongoing fashion following the September 5th launch, and developers will be welcome to submit Software titles via Steam Greenlight.

“The 40 million gamers frequenting Steam are interested in more than playing games,” said Mark Richardson at Valve. “They have told us they would like to have more of their software on Steam, so this expansion is in response to those customer requests.”